I have been asked to find out if there is a way to change the different user passwords for the HMI through the PLC. We use FactoryTalk View Studio for the HMI and rslogix5000 for the PLC. Currently we have to change the password in the HMI and then upload that program every time which is annoying. Is there a way to just change something in the PLC and have the password update automatically? I am pretty new to both PLC and HMI programming. Any help is appreciated.
Hi Alanze.
Firstly, welcome to the forum.
Yes this can be done, however I must state that there will not be any encryption or security regarding usernames or password, this data could be freely retrieved from the controllers memory.
So your looking at 2 bits of information per User, the username (STRING) and the password (you can restrict this to a signed/unsigned number if you wish or again use a STRING), maybe also an access level?. You could create this as a structure, then combine in an array.
ARRAY[0..15] of 'your structure name', this will give you 16 slots for users, obviously if you want more; you can just expand the array.
Then you just need some logic to verify the password they have entered matches what is stored in the PLC, if all is good then set whatever access level is given in their credentials. Further steps could be to monitor activity timeout, aswell as login/ logout and change password buttons.
Does this make sense to you?
If you need further informatio; just let me know.
Regards
Daniel